Cross-Modal Contributions to Episodic Memory for Voices

Multisensory context often facilitates perception and memory. In fact, encoding items within a multisensory context can improve memory even on strictly unisensory tests (i.e., when the multisensory context is absent). Prior studies that have consistently found these multisensory facilitation effects have largely employed multisensory contexts in which the stimuli were meaningfully related to the items targeting for remembering (e.g., pairing canonical sounds and images). Other studies have used unrelated stimuli as multisensory context. A third possible type of multisensory context is one that is environmentally related simply because the stimuli are often encountered together in the real world. We predicted that encountering such a multisensory context would also enhance memory through cross-modal associations, or representations relating to one's prior multisensory experience with that sort of stimuli in general. In two memory experiments, we used faces and voices of unfamiliar people as everyday stimuli individuals have substantial experience integrating the perceptual features of. We assigned participants to face- or voice-recognition groups and ensured that, during the study phase, half of the face or voice targets were encountered also with information in the other modality. Voices initially encoded along with faces were consistently remembered better, providing evidence that cross-modal associations could explain the observed multisensory facilitation.